Missing `Order` for `IsPlistMatrixRep`

[fingolfin]

gap> m:=Random(GL(64, 17^2));;
gap> Order(m);;
4506877618678682053501553567912215970985587762960033400213174378285090716039396133743908675760963910\
364731694730391071112617643214159971379423034880
gap> time;
414
gap> m2:=Matrix(m);
<64x64-matrix over GF(17^2)>
gap> Order(m2);  # does not terminate

The second Order computation has no chance to complete as it falls back to this:

    # Compute the order.
#T warnings about possibly infinite order ??
    pow:= obj;
    ord:= 1;
    while pow <> one do
    ord:= ord + 1;
      pow:= pow * obj;
    od;

[ThomasBreuer]

I think the point is that the methods for Order related operations are missing for all kinds of matrix objects, not only for IsPlistMatrixRep. Thus the task is to make the methods for Order, ProjectiveOrder, MinimalPolynomialMatrixNC, etc. applicable in a more general situation.

(For objects in IsCMatRep, Order works because they are also in IsMatrix, and because of a special MinimalPolynomialMatrixNC method.)